MSM MHI UCI interface device

MHI userpace control interface (UCI) enables userspace software clients to
communicate with device using MHI protocol.

==============
Node Structure
==============

Main node properties:

- compatible
  Usage: required
  Value type: <string>
  Definition: "qcom,mhi-uci"

- qcom,mhi-uci-channels
  Usage: required
  Value type: Array of <u32>
  Definition: Array tuples which define the channel configuration
	parameters.  Each tuple is of length 2, 1st value
	represent channel, and 2nd value represent maximum
	payload supported.  Maximum payload supported is 64
	bytes.  Number of tuples must be even value.  Max # of
	tuples is 46.

- qcom,mhi-uci-ctrlchan
  Usage: optional
  Value type: <u32>
  Definition: Channel that will be handling flow control (DTR/RTS) signals.

=======
Example
=======
qcom,mhi-uci@0 {
	compatible = "qcom,mhi-uci";
	qcom,mhi-uci-channels = <0 0x1000>,
				<1 0x1000>,
				<2 0x1000>,
				<3 0xffff>,
				<10 0x1000>,
				<11 0x1000>,
				<14 0x1000>,
				<15 0x1000>,
				<16 0x1000>,
				<17 0x1000>,
				<18 0x1000>,
				<19 0x1000>,
				<24 0x1000>,
				<25 0x1000>,
				<32 0x1000>,
				<33 0x1000>;
	qcom,mhi-uci-ctrlchan = <18>;
	status = "ok";
};